If $9a + 3b + 6c = -6$ and $2x + 4y = 2$, what is $-16y - 81a - 54c - 8x - 27b$ ?
Explanation: $= -81a - 27b - 54c - 8x - 16y$ $= (-9) \cdot (9a + 3b + 6c) + (-4) \cdot (2x + 4y)$ $= (-9) \cdot (-6) + (-4) \cdot (2)$ $= 54 - 8$ $= 46$